In order to produce inductive components, for example, an air coil or a transformer, it is necessary to deform a wire accordingly. In order to produce an air coil, the wire, for example, must be wound in a coiled manner. In order to produce a transformer it is necessary to wind the wire around a leg of the transformer. If the transformer has a closed core, an automated direct winding of the closed core poses a particular challenge.
Up to a certain ratio of wire cross section, winding spiral diameter, number of turns and core cross section, it is possible to a limited extent to “rotate” pre-shaped air coils onto a closed core of a transformer. The coiled air coil, which assimilates a tension spring, for this purpose must be spread apart until the core cross section can be overcome. During this process however, which is generally very complex and time-consuming, high mechanical forces act on the core that is to be wound. Due to the splaying of the “tension spring” to form a “compression spring”, the possible degree of filling of a closed core is necessarily limited or the “tension spring” produces mechanical stresses permanently. The ferrite core materials generally used for a transformer, however, are very sensitive with respect to the action of mechanical stresses.
The production of transformers that have a closed core and in which flat wires of rectangular cross section (rectangular wires) are used instead of round wires for the winding is particularly challenging. This transformer type enables the conduction of currents of high amperage with high inductance of the component caused by the high number of turns that can be attained. A rectangular or flat wire usually can no longer be applied to a closed core in an automated manner, and this is therefore generally very time-consuming.